Determining the area of your home lawn is an important factor in many management practices. For instance, if you plan to establish a new lawn, knowing the area of your lawn is necessary for calculating the amount of seed, sod or plugs needed. Lawn area is also required for any fertilizer or pesticide application calculation. Follow either of these two simple methods to estimate the area of your yard.
Most home lawns are not a perfect square or rectangle. However, a lawn area can be calculated using common shapes, such as rectangles, squares and circles. For example, one can estimate the area by breaking the lawn into smaller segments or shapes. Determine the area of the shapes and add the areas together to estimate the total lawn area.

Step 1: Determine the common shapes that will be used to estimate the area of the lawn.
Step 2: Take the necessary measurements of each shape to determine the area of each shape
Step 3: Complete the area calculations for each common shape and add the areas for a total area estimation.
Area of large rectangle = length x width - 30 feet x 15 feet = 450 square feet
Area of small rectangle = length x width - 15 feet x 10 feet = 150 square feet
Area of a circle = π r2 (assuming π = 3.14) - 3.14 x (14 feet)2 = 615 square feet
Total area = 1215 square feet
Another method for estimating a home lawn area is the offset method. This method requires you to measure a dissecting line across the longest axis, or distance, of the lawn area to divide the lawn into smaller, easier-to-measure segments. There are several simple steps to follow.

Step 1: Measure a line for the longest axis of the shape.
Step 2: Measure equally spaced, perpendicular lines that offset the axis line. The distance between the lines will be known as the h factor.
Step 3: Measure the distance of all offset lines.
Step 4: Add the distances of the offset lines together. Then multiply total offset line distances by h.
Area = ΣLines (h)
Area = (15 ft + 18 ft + 16 ft + 8 ft + 7 ft + 20 ft + 22 ft + 18 ft) x 10 ft
Area = (124 ft) x 10 ft
Area = 1,240 square feet
Download here: Louisiana Home Lawn Series: Estimating Lawn Areas 3624-GGG